Version:            (using KDE KDE 3.1)
Installed from:    Mandrake RPMs
OS:          Linux

It would be a really nice feature if you could add an option to rearrange the taskbar tasks: when you start a new application, it is automatically added to the right of the taskbar (if grouping is not involved). As far as I know there is not a single desktop environment that allows a user to reorder the contents of the taskbar. Reordering allows for a much prettier user experience as the user is now in control of 'grouping' similar tasks (that involve different programs) together on the taskbar. I'm not asking for a grouping function, just the ability to shuffle the icons/tasks in the taskbar possibly by using a drag and drop kind of interface.

To those who are interested: this feature is not available under GNOME, Mac OS X or (yeah I'm going to say it) Windows. It would mean a small opportunity to improve desktop friendliness.